If you don't understand what is going on with the price of gasoline and demand for the world's oil supply, then join the club.

Analysts, pundits, government officials, oil ministers, oil executives, and oil traders are all over the board in trying to explain what is happening and more importantly what is going to happen. Some are saying that $30 oil will be with us until the economy recovers while others are talking of a spike to $200 in 2009.

We are currently finishing out an extraordinary year. For several years now, oil prices have been moving steadily higher. They passed $100 a barrel around New Year's and moved on to peak at around $147 in July. By late spring much of the world was in turmoil. Politicians were out in force, bashing speculators, environmentalists, OPEC, additions to the Strategic Petroleum Reserve and you name it. Airlines and car sales were collapsing. The President flew off to Saudi Arabia where he personally appealed to the King to send us more oil. The King held a big oil conference and promised to do what he could.

Then, in mid-July, the great oil panic came to a screeching halt. While several explanations have been offered for this turnabout, I believe the start of the Beijing Olympics the most proximate cause. If 2008 has been hard on America it has been traumatic for China. In the first half of the year the Chinese endured a great earthquake, major snowstorms, and a nationwide panic over readiness to put on the Olympics. All this, of course, was accompanied by some of the worst air quality on earth.

For six months China was in an oil-buying frenzy trying to compensate for lost production during the quakes and storms, and ensuring that there would be no fuel shortages during the Olympics. To clean up the air, Beijing banned half the cars and trucks in and around the capital from operating and shut down every industrial enterprise that contributed to air pollution for hundreds of miles around the Olympic sites. The plan worked, but China's oil imports plummeted and the greatest oil price plunge in history began.

The great plunge was aided by the $4 to $10 gallon cost of gasoline and diesel in the U.S. and Europe which some believe was a primary cause for the world economy tanking in the second half of the year. To the surprise of nearly all observers, once oil prices began falling; they fell, and fell, and then fell some more. From $147 a barrel, prices dropped until they briefly touched $32 last week and are currently sitting around $40. To the delight of motorists, gasoline prices in the US went from $4 - $5 a gallon in July to $1 - $2 in December. Although it went unnoticed, America's economy received a massive stimulus from the billions of dollars that were left in consumers' pockets after each fill-up.

Now we get to the key question of why oil has fallen so low and the corollary of what happens next -- $20 or $200 oil. For the why-so-low question there can only be two answers: either demand has dropped well below readily available supplies or market factors such as speculation, trader pessimism, or the unwinding of hedge funds has caused oil to drop so rapidly.

Despite the lack of good information, it is clear that worldwide demand for oil has fallen in the last six months. U.S. demand is down about 1.2 million barrels a day(b/d). OECD commercial petroleum inventories, including those of the US have increased steadily as importers have taken advantage of lower prices. We know that Japanese imports are down around 500,000 b/d over last year and that Chinese imports have dropped a little. What is missing for now is a good feel for the actual size of the worldwide drop in demand. At one end of the scale is the IEA who recently opined that for 2008 worldwide demand will only be down by 200,000 b/d. Some, however, are saying demand is already 6 or 7 million b/d lower than the peak of around 86 million b/d reached last summer. This will take some time to sort out.

What is important, however, is that oil traders and the financial press continue to repeat over and over again that oil prices are dropping because of the contracting world economy. This has become the mantra of the market. There is also a substantial body of opinion that some component of the fall in oil prices is due to the unwinding of hedge funds and the general deleveraging of nearly all financial institutions.

While U.S. demand for oil products currently is down about 6 percent, this number has been stable for several months. Oil is so deeply ingrained in the fabric of most countries, particularly that of the U.S., that deeper cuts in consumption are unlikely unless the economy really sours.

OPEC production cuts are now approaching 2 million b/d and are scheduled to reach 4 million b/d in the next couple of months. Whether this will be enough to cover the drop in demand is the question of the day. Most commentators are fearlessly predicting a rapid rise in oil prices as soon as economic recovery sets in -- either in a few months or a couple of years. The more interesting issue is what happens if there is no recovery in the next few years or the next few decades. Do oil prices bounce merrily along at rock bottom levels until geological and investment constraints start to massively limit supplies? OPEC is already talking of yet another cut as the last three have had no measurable effect. Will OPEC overcut and cause another price spike within the next year despite the state of the economy?

There is clearly an irreducible minimum amount of oil consumption out there below which our oil-based economies will begin to deteriorate rapidly. If there is anything that is certain as a result of the present low oil prices, it is that investment in new oil production is dropping so rapidly that there will be serious problems three to five years from now.